Legend of Tarzan: Margot Robbie punched Alexander Skarsgård during a sex scene

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Few romances have been adapted for the screen as often as the saga of Tarzan and Jane — whether it’s Johnny Weissmuller telling Maureen O’Sullivan, “Me Tarzan, you Jane” in 1932’s Tarzan the Ape Man or Andie MacDowell teaching Christopher Lambert English in the 1984 Greystoke.

But when Harry Potter and the Deathly Hallows director David Yates set out to cast the leading lady in his upcoming blockbuster The Legend of Tarzan, he knew he needed a Jane who, yes, had chemistry with Alexander Skarsgård but could also fend for herself in the Congolian wilderness. He found both in Margot Robbie.

“If you enter the jungle with anybody, you want to go with Margot Robbie,” Yates says. “She’s practical, and she’s smart, and she’s resourceful. And she can take care of herself.”

As the Jane to Skarsgård’s Tarzan, Robbie is anything but a passive wife who sits around, waiting to be saved — even when Christoph Waltz’s villainous Leon Rom tries to use her as bait for her husband. (In the Tarzan trailer, she refuses to scream “like a damsel” when Rom commands her to.)

“It was very important that we didn’t want it to feel archaic or dated, where it’s like, tough guy has to save the poor girl,” Skarsgård says. “You have to feel that she’s strong and independent, and when you cast Margot, you’ll definitely get that.”

In fact, Skarsgård got a firsthand look at that strength in one particularly steamy scene.

“They’re doing this love scene together, and I said [to Robbie], ‘Just slap Alex while you’re making love, just kind of give him a punch,’” Yates explains. “It was sort of an earthy, sensual moment of her enjoying sex with Alex, and the only bruise he picked up during the entire shoot was probably that punch from Margot. Which says a lot about her feistiness.”